When Harold Shipman was jailed last January for the murder of 15 of his patients, he gained entry into an exclusive club - Britain's worst serial killers.

But if the Department of Health's suggestion that the former GP may have been responsible for as many as 250 deaths was accurate, he would be the UK's biggest mass murderer ever.

Although Shipman's murders involved the clinical dispatch of elderly patients through carefully administered drugs, the company he keeps in the annals of Britain's multiple killers boast a far more macabre catalogue of crimes.

For, while Shipman's motives remain relatively vague, the passions which drove others to kill have inspired some brutal and often inconceivable acts of evil.

Sutcliffe murdered 13 women

The niceties of Victorian society did little to contain the urges of poisoner Mary Ann Cotton who, more than 120 years after she was hanged in Durham jail, currently remains Britain's worst serial killer.

Convicted of six murders in 1873, Cotton is widely held to have sent more than 20 victims to an early grave.

Across a 20 year period, her life was marked by determined efforts to scale the social ladder and the number of husbands, children and relatives who died - of remarkably similar symptoms - in her presence.

Cotton was eventually caught when a post mortem examination on one of her children revealed arsenic poisoning as the cause of death.

Severed heads

Equally distasteful are the activities of Dennis Nilsen, who claimed to have killed 16 young men by luring them back to his flat in Muswell Hill, north London, before strangling them.

Nilsen calmly confessed to the murders when police were called in following the discovery of human flesh by a drains engineer investigating complaints of an unpleasant smell.

When challenged, Nilsen showed detectives body parts and a pair of severed heads he had yet to dispose of.

He was convicted of six murders and jailed for life in 1983.

Rest of the worst

John Childs: burned the bodies of his six victims at his east London flat. Jailed for life in 1980

Colin Ireland: terrorised London's gay community, torturing and killing five homosexuals. Jailed for life in 1993

Jack the Ripper: never identified or caught, he killed at least five women around London's East End in 1888

Beverley Allitt: personality disorder made her kill four children and make attempts on the lives of eight others. Currently serving 13 life sentences

Few serial killers can lay claim to the level of fear inspired by Peter Sutcliffe's reign of terror as the Yorkshire Ripper.

Sutcliffe became the subject of one of the largest police manhunts as he preyed on women across the north of England during the 1970s.

Though he later claimed he was driven to murder 13 women by messages from God, the Crown decided he was fit to face murder charges and sentenced him to no less than 30 years behind bars.

Probably the most notorious British serial killers of recent history are Fred and Rosemary West, whose names are synonymous with some of the most depraved acts ever detailed in court.

In their home in 25 Cromwell Street, Gloucester, they indulged their joint passions for sexual depravity and death.

When the investigation was launched into their activities, the nation watched aghast as body after body was exhumed from under their house.

Fred West eventually committed suicide before being brought to face charges of murdering 12 people, including his first wife and eldest daughter.

Rose West was convicted of 10 murders at Winchester Crown Court in November 1995 and is serving life in Holloway prison in north London.

'Acid bath vampire'

Among the more elaborate murderers lies John Haigh who was branded the "acid bath vampire" after claiming to drink the blood of the six victims he disposed of in vats of acid.

A forger and fraudster, Haigh befriended his victims before faking legal documents to secure money and possessions after their death.

Although he tried to plead insanity, he was convicted and hanged in 1949.

John Christie's activities around 10 Rillington Place, west London, in the 1940s, were morbidly fascinating enough to merit a toned-down film adaptation.

In the 1971 production Sir Richard Attenborough played the sinister landlord who gassed eight people and sexually interfered with their corpses. Christie was hanged in 1953.

Myra Hindley remains a figure of hate

The brutal murder of seven pensioners in south London saw Ken Erskine earn himself notoriety as the Stockwell Strangler.

Motivated mainly by the desire to get his hands on his victims' money, Erskine was jailed for 40 years in 1988.

Though well down on the list in terms of lives claimed, Moors murderers Ian Brady and Myra Hindley, both serving indefinite life sentences, remain two of Britain's most demonised figures.

Their attacks on five small children, whom they disposed of on Manchester's bleak Saddleworth Moor in the 1960s, scandalised the nation and continue to cause outrage.

But the body count notched up by all these killers pales into insignificance beside that widely attributed to Dr John Bodkin Adams.

Echoing Shipman's activities, Bodkin Adams was acquitted in 1953 of the murder of an elderly widow in Eastbourne.

But since his death evidence has emerged to suggest he may have helped up to 25 of his patients into their graves, after first influencing them to name him in their wills.

But Dr Bodkin Adams' activities pale into insignificance compared with those of Shipman, whose death toll may have been 10 times as many.